In U.S. Pat. No. 4,204,877, Moorer et al. disclosed that crude glycerin bottoms, which are chemically comprised of polyglycerol, can be used as cement grinding additives and set retarders in the manufacture of hydraulic cement. Moorer et al. further disclosed that the polyglycerols are preferably selected from di-, tri-, and tetraglycerols and mixtures thereof. They further mentioned that the use of polyglycerols helped to avoid “a significant loss of consistency shortly after mixing” and to provide longer “board life” (setting time). However, the present inventors believe that these set retarding effects are not always desirable; and, further, that the increased setting time conferred by polyglycerols may come with an undesired decrease in compressive strength.
An objective of the present inventors is, therefore, to control (reduce) the set retardation and to counter-act other effects of polyglycerols in cementitious materials.